Sterilization containers with a lower housing as well as a tightly attachable container cover have already been known for a long time and are used, for example, to sterilize medical devices. To guarantee ventilation and removal of air with the sterilization container closed, such sterilization containers are provided, in at least one of their wall areas, with gas exchange openings, which may be covered, for example, by means of a filter blade on the inside during the operation. As such a filter blade is to be replaced as the operating time increases, such a filter blade is held replaceably by means of a pressing disk on the side on the wall area. The pressing disk is correspondingly arranged on the inside on the wall area and detachably meshes with a frame element surrounding the gas exchange openings in a ring-shaped pattern. This detachable connection between the pressing disk and frame element can be established here by a bayonet connection, which is formed from bayonet catch elements or bayonet connection elements, which can be caused to mutually mesh with one another, on the pressing disk, on the one hand, and on the frame element, on the other hand. At least one sealing ring is provided to seal the pressing disk against the corresponding wall area of the sterilization container and against the frame element. This sealing ring is received on the wall side in a peripheral annular groove of the pressing disk or of the cover plate. To achieve good sealing action, this sealing ring presses in the mounted state the filter blade, which is inserted, in a relatively accurately fitting manner, into the ring-shaped frame element. The pressure disk thus forms, together with the filter blade and frame element, a kind of filter unit.
Based on the bayonet connection provided between the pressing disk and frame element, the pressing disk can be detached from the frame element and reinserted into same only by a relative rotary motion. Since the sealing ring of the pressing disk sealingly presses the filter blade, and the pressing disk can be correspondingly braced under an axial prestress against the filter blade, this relative rotary motion leads, especially during the mounting of the pressing disk, to a displacement of the filter blade and/or to damage thereto.
It would therefore be extremely advantageous to replace this bayonet connection by another type of connection in order to avoid such a destruction or displacement of the filter blade.
A sterilization container, which likewise comprises a box-like lower part and a container cover, which can be placed tightly on the lower part, is known in this connection from DE 20 2010 001 382 U1. However, instead of a filter blade, a so-called Pasteur loop is provided as the filter unit in this sterilization container. Such a Pasteur loop comprises, as a rule, two plates, namely, a base plate and a cover plate, which have concentric annular ribs each. These annular ribs of the base plate and of the cover plate mesh with one another with a radial clearance axially such that both axial and radial annular gaps are formed. Furthermore, a wall section of the container cover is provided in the area of this Pasteur loop with ventilation openings, through which ventilation and removal of air from the closed sterilization container take place during the operation. The air, which enters through the ventilation openings and flows through these annular gaps alternatingly radially and axially and finally enters the sterilization space and leaves the latter, is sterilized by the Pasteur loop.
The base plate, which is mounted on the wall element of the container cover on the inside by means of screw connections or the like, is designed as a complete, separate component with its annular ribs in the subject of DE 20 2010 001 381 U1. In one embodiment variant, the cover plate can be caused to lockingly mesh with the base plate by means of a plurality of spring-loaded locking balls distributed uniformly over the circumference. These locking balls are arranged here in an axially projecting, peripheral retaining ring, which surrounds the cover plate. Due to the base plate being designed as a separate component, it is possible to prepare, in particular, the cross holes for receiving the locking balls as well as the axial compression springs loading these in an extremely simple manner. However, it was found that it is absolutely necessary for this to design this base plate as a separate component and to prepare the corresponding cross holes in the edge web and to insert the locking balls before mounting. It is only thereafter that the base plate can be placed on the inside on the wall section of the container cover with the ventilating openings thereof. This special construction of the locking connection would also be able to be used to fix a filter blade. However, separate design of the base plate is always necessary here to make it possible to prepare the cross holes in the edge web.